Air-brake system.



PATENTED 'AUG. 4, 1903-.

w. B. MANN. AIR BRAKE SYSTEM. I APILICI.A'JJIOH' I'iLE-D JUNE 3,1903.

H0 MODEL.

INVENTOR WITNESSES.-

Atforneyd c. m: Noam vzrziws co, PHOTO-LIYNQ, WAS-(INGTON, o

Patented August 4, 1903.

PATENT OFFICE.

WILLIAM B.. MANN, OF BALTIMORE, MARYLAND.

AIR-*BRAKE SYSTEM.

SPECIFICATION forming part of Letters Patent No. 735,544, dated August4, 1903.

Application filed June 9,1969. Serial No. 159,920. (No model.)

To all whom, it may concern.-

Be it known that I, WILLIAM B. MANN, a resident of Baltimore, Maryland,have invented a new and useful Improvement in Air- Brake Systems, whichinvention is fully set forth in the following specification.

This invention relates to air-brakes, and more particularly to automaticair-brakes designed for conditions of use where it is undesirable tocarry an air-compressor on the car or train on which the brakes areemployed. In many cars, such as electric streetcars and electric carsgenerally, it has been proposed to employ an electric pump on the carfor compressing the air employed in operating the brakes. These pumpsare not altogether satisfactory in operation, are heavy and expensiveand give rise to a very disagreeble noise and jarring of the car. It hasheretofore been proposed to place a storagetank on each car which shouldbe charged with compressed air' at a central station and this chargeutilized as the braking power during a given run. This has manyadvantages over the proposal for carrying an electric aircompressor onthe car, since it is lighter, cheaper to install and operate, and isfree from jar and noise. There are, however, certain objections ordefects in the storagetank system as heretofore proposed which haveprevented its general or extensive use; and it is the object of thepresent invention to overcome these objections and eliminate the defectsto the end that this desirable system may be generally applied forstreet-car and suburban car service.

With this object in view the invention consists of a storage-tank ofrelatively large ca,-

pacity and of sufficient strength to enable it to safely carry aircompressed to a high degreeof say two hundred and fifty to six hundredpounds per square inch-which tank is located on a car and is providedwith connections leading through a suitable reducingvalve to theordinaryor any desired form of auxiliary reservoir, from which the airis admitted to the brake-cylinder through any suitable triple valve-forexample, the triple valve shown in my United States Patent No. 650,018.As now operated electric street and suburban cars are frequently run intrains of two or more cars, and the principal features of my inventionare designed to facilitate the use of the storage-tank system abovedescribed in such trains. Proper braking requires that each car of atrain should be provided with a separate auxiliary reservoir andbrake-cylinder, and economy and efficiency of operation demand that thebrakesof all the cars should be controlled through the medium of asingle motormans brake-valve. Moreover, since the amount of compressedair required to brake a plurality of cars exceeds the amount required tobrake one car it is necessary that means be provided whereby the airstored in each storagetank on the train can be utilized. I thereforeprovide a line of train-pipe connecting the several storage-tanks of thetrain to the end that the several tanks may constitute one combinedstorage-reservoir. In addition to thisI provide the usual train-pipeleading rearward through the train from the motormans brake-valve(corresponding to the engineers valve in steam-railway trains) to eachauxiliary reservoir. By this means all the air in the connectedstorage-tanks of the train isfed through a single motormans brake-valveto the train-pipe and thence to the auxiliary reservoirs. In order toretain the air in the several storage-tanks when the cars of the trainare uncoupled or the train is accidentally broken in two, I providemeans, preferably automatic, for closing the exit conduit or conduitsfrom each storagetank. Preferably, also, I provide each tank with anindependent connection between the tank and the train-pipe and areducing-valve and motormans brake-valve controlling said connection, sothat each individual car may have the means for efiectively operatingthe brakes of the entire train or the brakes of the said individual carwhen it is taken out of the train and run alone.

Other specific details of theinvention will be hereinafter described andthen defined in the claims. The inventive idea involved may receivevarious mechanical expressions, one of which is illustrated in theaccompanying drawings, in which- Figure 1 is a diagrammatic View showinga plurality of storage-tanks connected according to my invention incombination with the train pipe, auxiliary reservoirs, and

reservoir, 2 a brake-cylinder, and 3 an auxiliary reservoir of anysuitable or usual construction and all designed to be located on asingle car. The usual train-pipe 4 extends under the car and isconnected to the auxiliary reservoirthrough the branch pipe 5, in whichis a stop-cock 6. Another branch pipe 7 connects the storage-tank 1 withthe trainpipe 4, a reducing-valve 8 being interposed therein between thetank and pipe 4. On the train-pipe side of the reducing-valve 8 is amotormans brake-valve 9 of any desired construction for controlling thepassage of air from the storage-tank to the train-pipe to charge theauxiliary reservoir or the escape of air from the train-pipe to theatmosphere in operating the brakes. The train-pipe 4 is provided at eachend with coupling's 1O 10, whereby it may be connected to a liketrainpipe on another car, and the usual stop-cocks 11 11 to prevent theescape of air from the pipe 4 to the atmosphere.

As thus far described the construction relates to the equipment of asingle car, as illustrated in the right-hand section of Fig. 1, and theoperation is as follows: Assuming air in the storage-tank to becompressed, say, to thirty atmospheres, the cooks 11 11 closed, and themotormans valve set so as to permit air to pass from pipe 7 to thetrain-pipe 4, the reducing-valve 8 acts to permit air at any desiredpressuresa v sixty poundsto pass via pipes 7 and 4 to charge theauxiliary reservoir, and the air thus charged in the auxiliaryreservoiris utilized to apply the brakes by reducing the train-pipepressure through the motormans valve 9 in the usual and wellknownmanner. This combination of a storage-tank, reducing-valve, brake-valve,trainpipe, auxiliary reservoir, and brake-cylinder is old and wellknown, and I do not claim the same as of my invention.

\Vhen it is desired to unite a plurality of cars thus equipped into atrain, I provide a second line of pipe directly connecting thestorage-tanks in the several cars, such as the continuous pipe 12 ofFig. 4, with the branch pipes 13, leading therefrom to the storagetanks,or I connect the adjacent ends of the several tanks by sections of pipe14, as in Fig. 1, and in order that the air may not escape from theseveral tanks to the atmosphere when the cars of the train are separatedI interpose between the tank and the coupling ends of the second pipe 12or the sections 14 means for automatically preventing the escape of theair from the tank. Preferably this takes the form of a valve 15,interposed in the branch pipes 13 of Fig. 4.0r

placed at opposite ends of the tanks in the form shown in Fig. 1. Thepreferred construction of valve is shown in Fig. 2, wherein 16 is avalve-casing whose end 17 is adjacent to the storage-tank. In thiscasing the valve 15 has a seat 18 and a spring 19, acting to unseat thevalve toward storage-tank pressure. A by-pass 20 leads around the valve15, and a cock 21, with a conduit 22 therethrough, acts to open or closethe by-pass 20, depending upon the position of the cook 21. The stem 23of this cock extends out through the casing 16 and has handle 24attached thereto, whereby the cock may be manipulated. Preferably aspring 25, Fig 3, is applied, so as to normally hold the cock closed, asshown in Fig. 2.

The operation is as follows: The several cars of the train being coupledtogether, the sections of the train-pipe 4 being coupled, and thesections of the secondary pipe connecting the storage-tanks being alsocoupled, the valves 15 are held closed by reason of the fact that thepressure within the tanks overcomes the springs 19 and forces the valvesto their seats. The handle 24 of the cook 21' is is now turned in thedirection indicated by the arrow 26, Fig. 2, so as to open the bypass 20and permit storage-tank pressure to pass to the opposite side of valve15, and when the pressures on the two sides of the valve have been thusequalized the spring 19 acts to open the valve, thereby placing all thestorage-tanks in free communication via the connecting-piping. When thehandle 24 is released by the attendant, spring 25, Fig. 3, acts torestore the cock 21 to the position shown in Fig. 2 and close theby-pass. All of the motormans brake valves being in blank position,whereby pressure is prevented from passing from the storage-tanks viathe train-pipe to the auxiliary reservoirs, the brake-valve on the frontcar is turned to charging position and air passes out of the frontstorage-tank via the front brake-valve and the train-pipe and chargesall the auxiliary reservoirs in the Well-known manner, the pressure inall the storage-tanks being maintained uniform by reason of theirconnection. The lowering of pressure in the front storage-tank does notcause any of the valves 15 at the other tanks to close, because theaction is so gradual that equalization takes place past the valves 15without overcoming the spring 19. The combined volume of air in all thestorage-tanks is thus available for braking purposes. Should the trainbreak in two or the cars thereof be uncoupled forswitching onto branchlines or for other purposes, the valves 15 promptly close and preventwaste of air from the storagetanks on each car. Furthermore, each car isleft with a complete brake equipment, which may be used alone or incombination with another similarly-equipped car.

What is claimed is 1. In an air-brake system, the combination of aplurality of connected storage-tanks containing compressed air, andmeans preventing the escape of air therefrom when said tanks aredisconnected.

2. In an air-brake system, the combination of a plurality of connectedstorage-tanks containin g compressed air, and automatically-0peratingmeans preventing the escape of air therefrom when said tanks aredisconnected.

3. In an automatic air-brake system, the combination of a plurality ofcompressed-airstorage tanks, piping connecting said tanks, a brakingtrain-pipe in communication with said connected storage-tanks, aplurality of auxiliary reservoirs and brake-cylinders connected to saidbraking train-pipe, and a motormans brake-valve interposed between saidconnected tanks and the braking train-pipe.

4. In an automatic air-brake system, the combination of a plurality ofcompressed-airstorage tanks, a corresponding number of auxiliaryreservoirs and brake-cylinders, a trainpipe, communications between eachstorage-tank and the train-pipe and between each auxiliary reservoir andthe train-pipe, a motormans brake-valve interposed between eachstorage-tank and the train-pipe, and means connecting the severalstorage-tanks.

5. In an automatic air-brake system, the combination of a plurality ofcompressed-airstorage tanks, a corresponding number of auxiliaryreservoirs and brake-cylinders, a train-pipe, communications betweeneach storage-tank and the train-pipe and between 6. In an air-brakesystem, the combination of a plurality of storage-tanks for compressedair, open communications between said tanks, and a valve closing theexit from each stor age-tank'when said communications are severed.

7. In an air-brake system, the combination of a plurality ofstorage-tanks for compressed air, communications between said tanks, aninwardly-opening valve in said communications in proximity to each tank,and a spring tending to open said valve.

8. In an air-brake system, the combination of a plurality of storage-tanks for compressed air, communications between said tanks, aninwardly-opening valve in said communications in proximity to each tank,a spring tending to open said valve, a by-pass around said valve, and acock controlling said by-pass.

9. In an air-brake system, the combination of a plurality ofstorage-tanks for compressed air, a pipe-line extending along saidtanks, connections between said tanks and said pipeline,and acheck-valve preventing the passage of air through said connections whensaid pipe-line is severed.

10. In an air-brake system, the combination of a plurality ofstorage-tanks for compressed air, a pipe-line extending along saidtanks, connections between said tanks,and said pipeline, a check-valvepreventing the passage of air through said connections when saidpipeline is severed, and a normally closed bypass around said valve.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

" WILLIAM B. MANN.

Witnesses:

LEVEN J. GWINN, E. .T. GODMAN.

